JP2013084126A - Travel lane recognition device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine whether an object vehicle is traveling on the same lane as an own vehicle.SOLUTION: A travel lane recognition device (100) includes: acquiring means (14, 15, ANT) for acquiring a first speed pattern that is a speed pattern on a first vehicle (10, 30), and a second speed pattern that is a speed pattern on a second vehicle (20); and determination means (11) to determine, on the basis of similarity of the acquired first speed pattern and acquired second speed pattern, whether the first vehicle and second vehicle are traveling on the same lane.

Description

  The present invention relates to a technical field of a traveling lane recognition device that recognizes a lane in which a vehicle such as an automobile is traveling.

  As this type of device, for example, when the preceding vehicle detected by the radar is not located in either the own lane region or the other lane region determined from the detection range of the radar, the detected preceding vehicle and the own vehicle An apparatus has been proposed that determines whether a detected preceding vehicle is an own lane or another lane based on a relative speed with a vehicle (see Patent Document 1).

  Alternatively, the first other vehicle and the second other vehicle are compared by comparing the speed change of the first other vehicle detected by the autonomous sensor with the speed change of the second other vehicle acquired by inter-vehicle communication. Has been proposed (see Patent Document 2).

  A target speed pattern of the own vehicle is generated at any time based on the vehicle state and the external environment, and when driving in tandem with another vehicle, the platooning speed pattern is generated based on the target speed pattern of the own vehicle and the target speed pattern of the other vehicle. There has been proposed an apparatus that is generated as needed and performs vehicle travel control in accordance with the generated convoy travel speed pattern (see Patent Document 3).

  Alternatively, vehicle information including information on position and speed is acquired from a plurality of vehicles traveling on a road with a plurality of lanes, and the acquired vehicle information is classified into a plurality of classes according to speed levels, An apparatus has been proposed for determining which lane the vehicle information classified into a class corresponds to based on the information on the position and the position of the lane (see Patent Document 4).

  Alternatively, when the host vehicle changes lanes, the target acceleration / deceleration for inter-vehicle control for the preceding vehicle traveling in the original traveling lane and the target acceleration / deceleration for inter-vehicle control for the preceding vehicle traveling in the traveling lane after the lane change. There has been proposed an apparatus for controlling a host vehicle by comparing a speed and selecting a smaller target acceleration / deceleration (see Patent Document 5).

  Alternatively, an apparatus for measuring the arrival time difference of each data signal based on code sequence data signals transmitted from a plurality of road stations arranged on the road, and identifying a traveling lane based on the measured arrival time difference Has been proposed (see Patent Document 6).

Japanese Patent Application Laid-Open No. 06-191321 JP 2008-046873 A JP 2008-110620 A JP 2010-102575 A Japanese Patent Laid-Open No. 10-338055 JP 2000-076599 A

  However, the background art described above has a technical problem that it is difficult to determine with sufficient accuracy whether or not the target vehicle is traveling on the same lane as the own vehicle.

  The present invention has been made in view of the above problems, for example, and provides a traveling lane determination device that can accurately determine whether or not the target vehicle is traveling on the same lane as the own vehicle. Let it be an issue.

  In order to solve the above problems, a traveling lane recognition device according to the present invention includes a first speed pattern that is a speed pattern related to a first vehicle, and a second speed pattern that is a speed pattern related to a second vehicle. The first vehicle and the second vehicle travel on the same lane based on the similarity between the acquisition means to acquire, the acquired first speed pattern, and the acquired second speed pattern. Determining means for determining whether or not the

  According to the traveling lane recognition apparatus of the present invention, for example, the acquisition means including a memory, a processor, and the like is a first speed pattern that is a speed pattern related to the first vehicle and a speed pattern related to the second vehicle. And a second speed pattern. Here, the “speed pattern” means a temporal variation in speed within a predetermined period (for example, 60 seconds).

  The “first vehicle” may be a vehicle on which the travel lane recognition device is mounted, or may be a vehicle different from a vehicle on which the travel lane recognition device is mounted. When the first vehicle is a vehicle on which the travel lane recognition device is mounted, the acquisition unit acquires the first speed pattern based on a signal output from, for example, a vehicle speed sensor. On the other hand, when the first vehicle is a vehicle that is different from the vehicle on which the travel lane recognition device is mounted, the acquiring means is based on the relative speed detected by, for example, a millimeter wave radar or the like, or the inter-vehicle communication To obtain the first speed pattern.

  The “second vehicle” is typically in front of the first vehicle (one or a plurality of other vehicles may be present between the first vehicle and the second vehicle). Means a vehicle traveling on the road. The acquisition means acquires the second speed pattern using, for example, inter-vehicle communication.

  For example, the determination unit including a memory, a processor, a comparator, and the like may determine whether the first vehicle and the second vehicle are based on the similarity between the acquired first speed pattern and the acquired second speed pattern. It is determined whether the vehicle is traveling in the same lane.

  “Similarity” means an index indicating how similar the first speed pattern and the second speed pattern are to each other. Specifically, the “similarity” is, for example, (i) a correlation coefficient between the first speed pattern and the second speed pattern, and (ii) each of the first speed pattern and the second speed pattern at one time point. (Iii) a value obtained by integrating the absolute value of the speed difference for a predetermined period, (iii) a value obtained by integrating a value obtained by squaring the speed difference between the first speed pattern and the second speed pattern at one time point, for a predetermined period, and the like. Find it.

  According to the inventor's research, the following matters have been found. That is, when the vehicle density is high to some extent, the speed change in one vehicle propagates to the vehicle behind the one vehicle traveling in the same lane as the one vehicle. Therefore, the speed patterns of the two vehicles traveling on the same lane are similar to each other with a certain time delay. On the other hand, the similarity of the speed patterns of the two vehicles traveling in different lanes is low.

  For example, by using a vehicle-mounted camera or the like to recognize a white line drawn on the road, it is determined whether the vehicle traveling in front of the host vehicle is traveling in the same lane as the host vehicle. Although technology has been proposed, for example, when there are roads with relatively many curved sections, or when other vehicles exist between the vehicle and the target vehicle, the determination itself may be difficult There is a problem.

  Therefore, in the present invention, as described above, the first vehicle and the second vehicle are in the same lane based on the similarity between the acquired first speed pattern and the acquired second speed pattern by the determination unit. It is determined whether the vehicle is traveling.

  For this reason, it can be accurately determined whether or not the target vehicle is traveling on the same lane as the own vehicle. In particular, if the second speed pattern is acquired using inter-vehicle communication, the target vehicle (that is, the second vehicle) is relatively separated from the vehicle (that is, the own vehicle) on which the traveling lane recognition device is mounted. Even if the vehicle travels in a position (for example, 200 meters ahead), it can be accurately determined whether the target vehicle is traveling in the same lane as the host vehicle.

  In one aspect of the traveling lane recognition device of the present invention, the first vehicle is a vehicle on which the traveling lane recognition device is mounted.

  According to this aspect, the first speed pattern relating to the first vehicle can be acquired relatively easily, which is very advantageous in practice.

  Alternatively, in another aspect of the traveling lane recognition device of the present invention, the first vehicle is a vehicle traveling immediately before a vehicle on which the traveling lane recognition device is mounted, and the second vehicle is A vehicle traveling in front of the first vehicle.

  According to this aspect, even if the vehicle on which the travel lane recognition device is mounted performs, for example, ACC (Adaptive Cruise Control), the target vehicle is on the same lane as the own vehicle. Whether or not the vehicle is traveling can be determined with high accuracy.

  According to the research of the present inventor, when the ACC is implemented, the speed of the vehicle (that is, the own vehicle) on which the traveling lane recognition device is mounted changes relatively smoothly. It has been found that the correlation between the speed pattern and the speed pattern associated with the target vehicle (ie, the second vehicle) is relatively small. For this reason, the determination accuracy can be maintained by using the speed pattern relating to the vehicle traveling in front of the host vehicle (that is, the first vehicle).

  In another aspect of the travel lane recognition apparatus of the present invention, the determination means corrects one speed pattern of the acquired first speed pattern and the acquired second speed pattern, and then acquires the acquired speed pattern. The similarity between the first speed pattern and the acquired second speed pattern is calculated.

  According to this aspect, the similarity between the first speed pattern and the second speed pattern can be obtained relatively easily, which is very advantageous in practice.

  In this aspect, the determination unit may correct the one speed pattern by shifting the one speed pattern on the time axis.

  If comprised in this way, the similarity of a 1st speed pattern and a 2nd speed pattern can be calculated | required, reducing a processing burden.

  In this aspect, the determination means may determine an initial value of a shift amount when correcting the one speed pattern according to a distance between the first vehicle and the second vehicle.

  If comprised in this way, one speed pattern of a 1st speed pattern and a 2nd speed pattern can be correct | amended appropriately, and it is very advantageous practically.

  The effect | action and other gain of this invention are clarified from the form for implementing demonstrated below.

It is a figure which shows the mode at the time of driving | running | working on the road of the vehicle carrying the traveling lane recognition apparatus which concerns on 1st Embodiment. It is a block diagram which shows the structure of the traveling lane recognition apparatus which concerns on 1st Embodiment. It is an example of the graph which shows the time fluctuation | variation of the speed of the own vehicle, and the graph which shows the time fluctuation | variation of the speed of a communication vehicle. It is a figure which shows the graph which shifted the graph which shows the time fluctuation of the speed of the communication vehicle shown in FIG. 3 only for the predetermined time with the graph which shows the time fluctuation of the speed of the own vehicle shown in FIG. It is a figure which shows an example of correlation with the speed of the own vehicle and the speed of a communication vehicle. (A) is an example of the absolute value of the difference between the speed of the own vehicle and the speed of the communication vehicle, and (b) is an example of a value obtained by squaring the difference between the speed of the own vehicle and the speed of the communication vehicle. is there. It is a flowchart which shows the driving lane recognition process which concerns on 1st Embodiment. It is a flowchart which shows the driving lane recognition process which concerns on 2nd Embodiment.

  Hereinafter, an embodiment according to a traveling lane recognition apparatus of the present invention will be described with reference to the drawings. In the following drawings, members directly related to the present invention are shown, and other members are omitted as appropriate.

<First Embodiment>
1st Embodiment which concerns on the traveling lane recognition apparatus of this invention is described with reference to FIG. 1 thru | or FIG.

  As shown in FIG. 1, a vehicle 10 (hereinafter referred to as “own vehicle 10” as appropriate) on which the traveling lane recognition device 100 according to the present embodiment is mounted includes a plurality of vehicles (here, vehicles 20 and 30). Subsequently, it is assumed that the vehicle is traveling on the road. Here, it is assumed that the vehicle 20 is a vehicle equipped with a device capable of inter-vehicle communication (hereinafter referred to as “communication vehicle 20” as appropriate).

  FIG. 1 is a diagram illustrating a state when a vehicle 10 on which a traveling lane recognition device 100 according to the present embodiment is mounted is traveling on the road. Although not shown in FIG. 1, one or more vehicles exist between the vehicle 20 and the vehicle 30.

  Next, the configuration of the traveling lane recognition device 100 will be described with reference to FIG. FIG. 2 is a block diagram illustrating a configuration of the traveling lane recognition device 100 according to the present embodiment.

  In FIG. 2, the traveling lane recognition device 100 includes an ECU (Electronic Control Unit) 11, a storage device 12, an in-vehicle clock 13, a vehicle sensor 14, a millimeter wave radar 15, and an antenna ANT. Instead of the in-vehicle clock 13, a clock incorporated in a navigation device (not shown) may be used.

  The antenna ANT sequentially receives signals indicating speed information, vehicle ID (Identifier), position information, and the like related to the communication vehicle 20 transmitted from the communication vehicle 20. The speed information, vehicle ID, position information and the like related to the communication vehicle 20 received via the antenna ANT are stored in the storage device 12 in association with the time indicated by the in-vehicle clock 13.

  The vehicle sensor 14 detects the speed and traveling position of the host vehicle 10. The millimeter wave radar 15 is a distance between the vehicle (in this case, the vehicle 30) traveling immediately before the host vehicle 10 and the host vehicle 10 (that is, an inter-vehicle distance) and a relative speed of the vehicle 30 with respect to the host vehicle 10. Is used to detect.

  The ECU 11 changes the time variation of the speed of the host vehicle 10 detected by the vehicle sensor 14 (corresponding to the “first speed pattern” according to the present invention) and the time variation of the speed of the communication vehicle 20 acquired via the antenna ANT. It is determined whether or not the host vehicle 10 and the communication vehicle 20 are traveling in the same lane based on the similarity to the “second speed pattern” according to the present invention.

Specifically, the ECU 11 firstly changes the speed of the speed of the host vehicle 10 (refer to “v _self ” in FIG. 3) and the speed of the speed of the communication vehicle 20 from the current time to a predetermined time before (see FIG. 3). In “v _com ”). Next, the ECU 11 shifts the time variation of the speed of the communication vehicle 20 by a predetermined time with respect to the time variation of the speed of the vehicle 10 in consideration of, for example, the distance between the vehicle 10 and the communication vehicle 20. After that (see FIG. 4), the similarity between the time variation of the speed of the host vehicle 10 and the time variation of the speed of the communication vehicle 20 is obtained.

  FIG. 3 is an example of a graph showing the time variation of the speed of the host vehicle 10 and a graph showing the time variation of the speed of the communication vehicle 20. FIG. 4 is a diagram showing a graph obtained by shifting the graph showing the time fluctuation of the speed of the communication vehicle 20 shown in FIG. 3 by a predetermined time together with the graph showing the time fluctuation of the speed of the host vehicle 10 shown in FIG. It is.

Here, for example, as shown in FIG. 5, the correlation between the speed (v _self ) of the _host vehicle 10 and the speed (v _com ) of the communication vehicle 20 is obtained, and the correlation coefficient of the obtained correlation is similar. It may be used as an index indicating sex. In this case, if the value of the correlation coefficient is equal to or greater than a predetermined value (for example, 0.85), the ECU 11 determines that the host vehicle 10 and the communication vehicle 20 are traveling in the same lane. FIG. 5 is a diagram illustrating an example of a correlation between the speed of the host vehicle 10 and the speed of the communication vehicle 20.

Alternatively, for example, as shown in FIG. 6A, a value obtained by integrating the absolute value (| v _com −v _self |) of the difference between the speed of the host vehicle 10 and the speed of the communication vehicle 20 at one time point for a predetermined period. May be used as an index indicating similarity. Alternatively, for example, as shown in FIG. 6B, a value ((v _com −v _self ) ² ) obtained by squaring the difference between the speed of the host vehicle 10 and the speed of the communication vehicle 20 at one point in time is a predetermined period. The integrated value may be used as an index indicating similarity.

  In this case, the ECU 11 determines that the host vehicle 10 and the communication vehicle 20 are traveling in the same lane if the index indicating similarity is equal to or less than a predetermined value. 6A is an example of the absolute value of the difference between the speed of the host vehicle 10 and the speed of the communication vehicle 20, and FIG. 6B is the difference between the speed of the host vehicle 10 and the speed of the communication vehicle 20. Is an example of a squared value.

  Or it is good also considering the difference of the average value of the speed of the own vehicle 10 and the average value of the speed of the communication vehicle 20 in a predetermined period as a parameter | index which shows similarity. In this way, in particular, when the speed fluctuation of at least one of the own vehicle 10 and the communication vehicle 20 is relatively small, the vehicle 10 and the communication vehicle 20 are traveling in the same lane relatively easily. It can be determined whether or not. In this case, if the difference between the average value of the speed of the own vehicle 10 and the average value of the speed of the communication vehicle 20 is smaller than a predetermined value (for example, 5 km / h), the ECU 11 Are determined to be traveling in the same lane.

  The ECU 11 determines whether or not the host vehicle 10 and the communication vehicle 20 are traveling in the same lane based on the positional relationship between the host vehicle 10 and the communication vehicle 20 in addition to the index indicating similarity. May be. Specifically, for example, when the communication vehicle 20 located in front of the host vehicle 10 moves to the rear of the host vehicle 10 (that is, when the host vehicle 10 overtakes the communication vehicle 20), the ECU 11 It is determined that the vehicle 10 and the communication vehicle 20 are traveling in different lanes.

  The “vehicle sensor 14” and the “antenna ANT” according to the present embodiment are examples of the “acquiring unit” according to the present invention. The “own vehicle 10”, “ECU 11”, and “communication vehicle 20” according to the present embodiment are examples of the “first vehicle”, the “determination unit”, and the “second vehicle” according to the present invention, respectively. . In the present embodiment, some of the functions of the members constituting the host vehicle 10 are used as at least part of the traveling lane recognition device 100.

  Next, a travel lane recognition process performed by the travel lane recognition device 100 mounted on the host vehicle 10 configured as described above will be described with reference to the flowchart of FIG.

In FIG. 7, first, initialization is performed (step S101). This initial setting is typically performed by the manufacturer when the traveling lane recognition device 100 is manufactured. Items set in the processing of step S101 include, for example, determination time T ₀ (initial value is, for example, 50 seconds), shift time step ΔT (initial value is, for example, 0.5 seconds), determination threshold r ₀ (initial value) Is, for example, 0.8).

Next, the ECU 11 determines a maximum value T _max of the shift amount (step S102). Specifically, the ECU 11 communicates with the own vehicle 10 and the communication vehicle based on, for example, the traveling position of the own vehicle 10 detected by the vehicle sensor 14 and the traveling position of the communication vehicle 20 acquired via the antenna ANT. The distance Δx between the vehicle and the vehicle 20 is obtained, and the acceleration / deceleration propagation time Δt (that is, the human reaction time) is obtained by dividing the obtained distance Δx by the vehicle head distance ΔS per vehicle (for example, 20 meters). : For example, a value multiplied by 1 second (that is, Δx ÷ ΔS × Δt) is set as the maximum value _Tmax .

Here, ECU11 is good also considering the vehicle head space | interval (DELTA) S as a variable value according to the present speed of the own vehicle 10 or the communication vehicle 20, or the average value of the current speed of each of the own vehicle 10 and the communication vehicle 20. Since the vehicle head interval ΔS changes according to the speed of the vehicle, if the vehicle head interval ΔS is a variable value, the maximum value T _max of the shift amount can be determined more appropriately.

Specifically, the vehicle head interval ΔS = S ₀ / (v ₀ −v) may be set with S ₀ and v ₀ as constants. “V” is an average value of the current speed of the host vehicle 10 or the communication vehicle 20 or the current speed of each of the host vehicle 10 and the communication vehicle 20. Further, “v <v ₀ ”.

The ECU 11 further sets the propagation time Δt to (i) the current speed of the host vehicle 10 or the communication vehicle 20, or the average value of the current speed of each of the host vehicle 10 and the communication vehicle 20, and (ii) the vehicle head interval ΔS. It is good also as a variable value according to it. The propagation time Δt is considered to be smaller as the vehicle speed is larger and smaller as the vehicle head interval ΔS is smaller. Therefore, if the propagation time Δt is a variable value, the maximum value T _max of the shift amount is more appropriately determined. be able to.

Next, the ECU 11 acquires the current time T from the in-vehicle clock 13 (step S103). Subsequently, the ECU 11 determines the speed v _{selff of the host} vehicle 10 (that is, the speed pattern of the host vehicle 10 for the determination time T ₀ ) from the current time T to a time point that is back by the determination time T ₀ (ie, T−T ₀ ). ) Is acquired (step S104).

Subsequently, the ECU 11 sets an initial value T _min of the shift amount (step S105). Here, the initial value T _min of the shift amount may be set based on the same idea as the maximum value T _max of the shift amount described above. However, it is necessary to make fine adjustments such as setting the vehicle head interval ΔS to the longest in a range in which the speed fluctuation of the vehicle traveling in front of the host vehicle 10 affects the traveling of the host vehicle 10.

Next, the ECU 11 sets the initial value T _min of the set shift amount as the shift amount T ₁ . Subsequently, the ECU 11 starts from the time point that is shifted by the shift amount T ₁ from the current time T (ie, T−T ₁ ) to the time point that is further advanced by the determination time T ₀ (ie, T−T ₁ −T ₀ ). The speed v _com of the communication vehicle 20 (that is, the speed pattern of the communication vehicle 20 for the determination time T ₀ ) is acquired (step S106).

  Next, the ECU 11 obtains a similarity r between the speed pattern of the host vehicle 10 acquired in the process of step S104 and the speed pattern of the communication vehicle 20 acquired in the process of step S106 (step S107). . Here, it is assumed that the similarity r is obtained from the correlation between the speed of the host vehicle 10 and the speed of the communication vehicle 20 as shown in FIG.

Incidentally, ECU 11, when obtaining the similarity r, for example, the speed pattern of the vehicle 10, the time _{T-T 0} "0", the time T between _{"T 0",} the speed pattern of the communication wheel 20 The time T-T ₁ -T _{0 is changed} to “0”, and the time T-T ₁ is changed to “T ₀ ”, respectively.

Then, ECU 11 is the determined degree of similarity r determines whether the threshold value _{r 0} or more (step S108). If the determined similarity r is determined to be the threshold value _{r 0} or more (step S108: Yes), ECU 11, the communication wheel 20, traveling in the lane in the same lane on which the vehicle 10 is traveling (Step S109).

On the other hand, if the determined similarity r is determined to be less than the threshold value _{r 0} (Step S108: No), ECU 11 is increased by the step ΔT time shifting the shift amount _{T 1} (i.e., shift amount T ₁ is updated) (step S110). Subsequently, ECU 11 may shift amount _{T 1} that is updated, it determines whether the maximum value _{T max} is greater than or not the shift amount determined in the processing in step S102 (step S111).

If shift amount _{T 1} which is updated is determined to the maximum value _{T max} is greater than the amount of shift (step S 111: Yes), ECU 11, the communication wheel 20 is different car than the lane that the vehicle 10 is traveling It is determined that the vehicle is traveling on the line (step S112). On the other hand, if the updated shift amount _{T 1} is is determined to be less than or equal to the maximum value _{T max} of the shift amount (step S 111: No), ECU 11 performs the process of step S106.

Second Embodiment
A second embodiment of the traveling lane recognition device of the present invention will be described with reference to FIG. The second embodiment is the same as the configuration of the first embodiment except that the traveling lane recognition process is partially different. Therefore, in the second embodiment, the description overlapping with that of the first embodiment is omitted, and the common portions in the drawing are denoted by the same reference numerals, and only the points that are basically different refer to the flowchart of FIG. To explain.

In FIG. 8, after the process of step S <b> 103 described above, the ECU 11 determines the speed of the vehicle 30 that travels immediately before the host vehicle 10 until the time point that is a determination time T ₀ from the current time T (that is, T−T ₀ ). (That is, the speed pattern of the vehicle 30 for the determination time T ₀ ) is acquired (step S201). Next, the ECU 11 performs the process of step S105 described above.

  Here, the speed of the vehicle 30 may be obtained based on the relative speed of the vehicle 30 with respect to the host vehicle 10 detected by the millimeter wave radar 15 (see FIG. 2).

  The “millimeter wave radar 15”, “vehicle 30” and “speed pattern of the vehicle 30” according to the present embodiment are respectively “acquisition means”, “first vehicle” and “first speed pattern” according to the present invention. It is another example.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. The apparatus is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Own vehicle, 11 ... ECU, 12 ... Memory | storage device, 13 ... Car interior clock, 14 ... Vehicle sensor, 15 ... Millimeter wave radar, 20 ... Communication vehicle, 30 ... Vehicle, 100 ... Traveling lane recognition apparatus, ANT ... Antenna

Claims (6)

An acquisition means for acquiring a first speed pattern that is a speed pattern related to the first vehicle and a second speed pattern that is a speed pattern related to the second vehicle;
Based on the similarity between the acquired first speed pattern and the acquired second speed pattern, it is determined whether or not the first vehicle and the second vehicle are traveling in the same lane. Determination means to perform,
A travel lane recognition device comprising:   The travel lane recognition device according to claim 1, wherein the first vehicle is a vehicle on which the travel lane recognition device is mounted. The first vehicle is a vehicle traveling immediately before a vehicle on which the traveling lane recognition device is mounted,
The travel lane recognition device according to claim 1, wherein the second vehicle is a vehicle traveling in front of the first vehicle.   The determination unit corrects one speed pattern of the acquired first speed pattern and the acquired second speed pattern, and then acquires the acquired first speed pattern and the acquired second speed pattern. The travel lane recognition device according to any one of claims 1 to 3, wherein similarity with the other speed pattern is calculated.   The travel lane recognition device according to claim 4, wherein the determination unit corrects the one speed pattern by shifting the one speed pattern on a time axis.   6. The determination unit according to claim 5, wherein the determination unit determines an initial value of a shift amount when correcting the one speed pattern according to a distance between the first vehicle and the second vehicle. The travel lane recognition device described.

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